Altiris DS 6.9 SP5 and Mac 10.8

We're about to rollout new Macs running Mac OS X 10.8 but I can't get these Macs to connect to the server which runs DS 6.9 SP5 Build 517 (MR2). Older Macs running 10.5 - 10.7 work fine.

Note, we only use Altiris to collect inventory information. Deployment of Macs is handled by Apple software.

All Macs version have 'altiris-adlagent-2.6-92' installed but we get the following error in the client log with 10.8 Macs:-

[221 2013-04-06 17:28:08.245544 c8bcc89badf2 adl_session] Debug: Error:Operation timed out, connecting socket 3 to host at x.1x.x.x 402 ...
[221 2013-04-06 17:28:13.246287 c8bcc89badf2 adl_session] Warning: Error unable to connect to server
[221 2013-04-06 17:28:13.246516 c8bcc89badf2 adl_session] Debug: Error in ../common/tcp.c: Unable to set socket option to linger the address! Error: Invalid argument[221 2013-04-06 17:28:13.246575 c8bcc89badf2 adl_session] Debug: Can't set socket option:
[221 2013-04-06 17:28:13.246632 c8bcc89badf2 adl_session] Debug: -1 = Close( 3 )
[221 2013-04-06 17:28:18.247301 c8bcc89badf2 adl_session] Debug: Open socket for: x.x.x.x 402 ...
[221 2013-04-06 17:28:18.247527 c8bcc89badf2 adl_session] Debug: Connecting to host: x.x.x.x 402 ...

How do I get this to work? Is a new agent available? Do I need to update Altiris?